DHCP Snooping (Option 82?)

[jeasterwood]

I'm looking for a switch that will do the following:

     1.  Restrict certain ports to only 1 IP address.  For example Port 1 can only have IP of 10.5.13.101, Port 2 can only have IP of 10.5.13.102, etc.

     2.  Assign IP addresses to a workstation using DHCP regardless of the MAC address.

Here's the situation.  I've got a handful of workstations that will be mobile so to speak.  On any given day, they could move to a different place within a building to be used.  So we are going to have Cat6 cables run to each of these stations, and once you bring this "mobile workstation" to a location with a hook up, you just plug it in and your workstation is assigned an IP address based on your exact location (because of the port on the switch) and you're ready to go.  This needs to be done no matter which workstation is plugged in (So if workstation 1 is plugged into port 1 of the switch, it gets IP 10.5.13.101.  If workstation 3 gets plugged into port 1 of the switch, it gets IP 10.5.13.101).  From what I have researched, it seems this would be a little easier if each workstation had a static IP and it's just verified to be within a correct range, but I'm just not sure if you can use the switch to assign the workstation one IP address one one port, then when it moves to another port, it's assigned one separate IP address.  I've done a little research and I've found that you can do something close to this using DHCP Snooping to set a range of IP addresses per port (in my case, the range would just be 1).  I only know enough about networking to get myself in trouble, so I was hoping to enlist the help of some people who know more than I do

My real questions are is this possible, and if so, what features do I need to make sure my switch supports in order to make this happen?  Do I just need a switch that supports DHCP Snooping and set my workstations to obtain an IP address automatically?  Anything else? 

Thanks for your help.

[cadet alain]

Hi,

I don't think DHCP snooping is what you need.This feature is for alleviating DHCP starvation and Rogue DHCP attacks used for Man in the Midlle.It can also be used with IP Source guard feature to prevent IP spoofing also used in MiM attacks.

Will there be  only one Vlan for all the ports the machine will be plugged into?

Why not associate MAC address of machine to DHCP address in scope?

Regards.

Alain.

[jeasterwood]

I don't want to associate the MAC address of a machine to a DHCP address because the MAC address will be changing depending on which machine is connected.  For my application I need one room to only have one IP address and a separate room to only have a different IP address.  The application that I'm using gives you different features depending on what IP address you have, and I need it that way.

As far as the VLAN question, I'm not sure to be honest.  I need all of these mobile workstations to be able to communicate with each other and with a central workstation.